The present invention relates to a force reducing device for adjusting shutter ropes, wherein, in addition to pulling a shutter with less force, the shutter can be assembled easily.
Shutters of large size cannot be used to replace cloth window curtains due to the large force necessary to operate the rope of the shutters. The current force reducing device for shutters has pulleys in the lower beam thereof. The ropes pass through the same holes in the slats, so that the holes must be elongated. In addition to being difficult to assemble, the strength of each of the slats is weakened. In order to reduce the required force, the length of the rope must be elongated in an inverse ratio to the amount of fore reduction. However, a long rope spoils the appearance of the shutters. Furthermore, the operation of those shutters is inconvenient.
Accordingly, the primary object of the present invention is to provide a force reducing device for adjusting shutter ropes, wherein, in addition to pulling shutter ropes with less force, the shutters can be assembled easily.
To achieve that object, the present invention provides a force reducing device, for adjusting shutter ropes and the method thereof.
An upper beam is embedded with a plurality of pulley boxes, a slat angle drive, a plurality of winding boxes and a rope retaining seat. Each winding box has a rolling shaft. The rope retaining scat has a balance strip. A lower beam has a plurality of holes and a plurality of pulleys. A plurality of slats each have holes formed therethrough. The winding boxes are divided into two sets. The two winding box sets arc symmetrically arranged with respect to a center of the upper beam, and each winding box set is fixed with a respective rope. The two ropes pass through respective holes in the slats, and then wind through a first pulley on the lower beam. Then, the ropes extend and wind through a second pulley of the same set with the first pulley on the lower beam. The two ropes then pass upwards through the respective holes on the slats, and then pass through the upper sides of a rolling shaft below the winding boxes. The two ropes pass through outlets at an upper and a lower side of the balance strip, and then the two ropes arc combined as a first combined rope. Then, the first combined rope passes through an opening at another side of the rope retaining seat to be coupled to opposing ends of another rope to form a second combined rope. When the second combined rope is pulled, one end of the rope will lift the shutter, and another end of the rope will be received in an inner space of the upper beam.
The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawings.